He’s introducing the bulk of the Grant Grill’s spring offerings: new meats, new seafood. All accessorized with the first fruit, vegetables and edible flowers of the season.

It’s almost five years into Kurth’s tenure as chef de cuisine at the U.S. Grant Hotel’s storied restaurant. But this part is still nerve-racking, he’ll admit.

“You want everything to be right, on point, special,” says Kurth. At 36, he’s still getting his chef’s legs in his first kitchen leadership position.

“You guys ready to do this?” Kurth asks the six people standing in the kitchen, opposite the 45-foot-long hot line where the food is cooked. It’s 5:30 p.m. on a Saturday and the front-of-the-house staff gathered here is buoyant.

While the chef’s tasting menu changes every week, a big overhaul like this only happens every quarter. Suddenly, O’Hara announces, “It’s my favorite day of the year!”

The server’s enthusiasm doesn’t match the chef’s mood.

Kurth’s sleeves are rolled up. The collar on his chef coat looks fatigued. His white apron is smudged with color. Kurth’s usually calm face, accented with sideburns, is almost cheerless as he lays out his latest creations along a stainless-steel counter, including the 15-ounce, dry-aged rib-eye that will be served with yellow foot chanterelle mushrooms, marrow and wild leeks.

“Oh! I forgot,” Kurth says, shaking his head. He walks back toward the cooking area like a father who started a household project without a vital tool. “You always forget something,” he says to himself, looking for citrumelo zest for the roasted lamb loin.

The lamb will reach the dining room as part of an amazingly pastoral dish, served with Kurth’s house-made ricotta-like milk curd, English peas, and, in a corner of the plate, a savory tart overflowing with Picholine olive mousse and poached cherry tomatoes. Despite his general humility, Kurth will allow that he’s pretty happy with the lamb.

Zest retrieved, Kurth is back in front of people eager to take up their Hepp-brand hotel silverware and sample the debuting dishes.

“I just love chef’s food,” says O’Hara, grinning.

“Now we’re ready,” Kurth says. “You guys ready for the rib-eye?”

The Grant Grill may sound like a place that flips burgers, but it’s an institution within an elegant, 100-year-old hotel. The restaurant has been open since 1951 and was a good ol’ boys’ club that banned women until 1964 (a year notable for a civil-rights act that barred workplace discrimination).

The Grant Grill used to be known for power-lunching and tableside Caesar salads. And it will forever be the home of the Grant Grill Mock Turtle Soup. After the Sycuan Band of the Kumeyaay Nation finished a multimillion-dollar renovation of the U.S. Grant in 2006 — the year Kurth came onboard — his executive chef took the mock-turtle soup off the Grant Grill menu.

The soup has long been reinstated. Under Kurth, it’s tangy, full-bodied like a long-simmered rich stew, and made with short ribs and cow tongue, not turtle.

Like many contemporary California chefs, Kurth is tastefully exploring offal. His Swiss grandmother introduced him to forcemeats; she made pâtes. For the Grant Grill, he makes crispy pork — tongue, cheeks and trotter made into a delicate, round croquette.

Kurth is also part of the farm-sourced ingredients cult, something he has in common with the first-class San Diego chefs with whom he apprenticed. Jeff Jackson at The Lodge at Torrey Pines taught him a respect for food, Kurth says. Paul McCabe, his old chef at L’Auberge Del Mar, remembers how careful and well-versed Kurth was with product.

But temperamentally, Kurth is probably more like the French master chef he reveres: Michel Bras, known as an artist-monk, a reclusive chef.

Mushroom Custard with Spring Green Salad

Serves 2

5 eggs

3 tablespoons flour

1 cup crème fraîche

1 cup whole milk

1 teaspoons salt

1/2 teaspoon fresh ground

pepper

1 tablespoon chopped thyme

2 cups of mushrooms sliced

Blended oil (or olive oil) for

sautéing mushrooms

1/2 cup shelled pistachios

Bibb or butter-leaf lettuce, pull off five leaves

Arugula flowers, for garnish

1/2 cup green grapes, sliced

Preheat oven to 295 degrees. Mix 1 egg and the flour in mixing bowl until smooth, then add the rest of the eggs and whisk to combine. In another mixing bowl, whisk the crème fraîche until it is smooth, then add the milk and whisk again. Next combine the contents of the two bowls, and add the salt, pepper and thyme.

Sauté the mushrooms in a tablespoon of oil; chop half of the cooked mushrooms and reserve the rest for garnish. Blend chopped mushrooms into custard mix.

Pour the mixture into two buttered and floured oven-safe soufflé dishes or two ramekins. Place the dish into a water bath (a pan big enough to hold the baking dishes, with warm water in the container up to the halfway line of the soufflé dish or ramekins) and bake until the custard has just set — touch it after seven minutes to see if it’s firm. The custard should slide out once it is done.

To serve, arrange the lettuce on two plates with your choice of dressing and place the custard in the middle of the plate; add the grapes and pistachios, and garnish with mushrooms and arugula flowers.

Back in the kitchen, Kurth stands back and watches as the Grant Grill staff carves into his dishes. They walk past and sample each plate like it’s a buffet line.

Put spices (cinnamon, cloves, bay leaf, thyme) in a sauté pan. Next, julienne the onions and add to the sauté pan with a half tablespoon of butter. Bring the pan to a low heat, season and stir occasionally; cook until the onions are golden brown. Next deglaze with the sherry; reduce the liquid by half. Add the chicken stock and simmer about 40 minutes until the flavors have blended.

In a small sauce pan add the vinegar and the water and bring to a low boil. Crack the eggs one at a time into the vinegar and water and cook until the eggs feel just firm — they should have the slightest bit of resistance when you touch them. Use a slotted spoon to remove the eggs and set aside. Using the slotted spoon, scoop half of the cooked onions into the middle of each of two soup bowls, then pour the broth over the onions. Add a cooked egg to each bowl, and garnish with the fresh herbs, shaved cheese and the hazelnut oil.